Foundation November 2020 Paper 1 Q28
28 Rearrange \(\quad c = \dfrac{d + 2}{3} \quad\) to make \(d\) the subject. [2 marks]
| Answer | Mark | Comments |
|---|---|---|
| Alternative method 1 | ||
| \(3c = d + 2\) or \(3c - 2\) | M1 | |
| \(d = 3c - 2\) or \(d = -2 + 3c\) or \(3c - 2 = d\) or \(-2 + 3c = d\) | A1 | |
| Alternative method 2 | ||
| \(c - \dfrac{2}{3} = \dfrac{d}{3}\) or \(3\left(c - \dfrac{2}{3}\right)\) | M1 | |
| \(d = 3\left(c - \dfrac{2}{3}\right)\) | A1 | |
Additional guidance
| Flow chart method, with incorrect final answer: \(d \to +2 \to \div 3 \to c\) and \(c \to \times 3 \to -2 \to d\) | M1A0 |
| Condone \(\times\) signs for M1 but not A1 Condone \(c3\) for M1 but not A1 |